How much do you know about cryptocurrencies? Even if you don’t know much you are very likely to have heard about the most popular member of the family: Bitcoin. Bitcoin (BTC) has been around for some time now (see the blog Bubbling Bitcoin). It was first released in 2009 by its inventor (the mysterious Satoshi Nakamoto, whose real identity still remains unknown), and since then it has gradually increased in popularity.

According to the Bitcoin Market Journal (a specialised blog, commenting on trends in digital currencies – primarily Bitcoin), there are currently about 29 million digital wallets holding at least 0.001 BTC, although some individual users may own multiple wallets.

Although BTC is the most popular digital currency (and the first one to become widely recognisable), it is certainly not the only one. There are currently more than 400 recognisable cryptocurrencies traded in special digital exchanges (twice this number if you count smaller, less successful ones) with a total capitalisation of $700 billion at its peak (January 3, 2018) – although since then the market has lost a significant part of this value (but it’s still worth 100s of billion of US dollars).

If you have heard about Bitcoin before, chances are you first searched for it sometime between December 2017 and January 2018; that is when the value of Bitcoin soared to $20 000 a piece. A search on Google Trends (a Google utility that shows how many people have searched over a period of time for a certain term – in this case “Bitcoin”) shows this very clearly.

So what do people do with Bitcoin and other cryptocurrencies? The truth is that the majority of users use them for speculative purposes: they buy and sell them, in the hope of making a profit. Due to its extreme volatility (it is very common for the price of the larger cryptocurrencies to fluctuate by 10–20% daily) and the unregulated nature of the cryptocurrency market, it is hardly surprising that most users treat them as very high-risk commodity. This is also why digital currencies tend to attract attention (and new users) when their price soars.

However, cryptocurrencies are not only used for speculation. They can also be used to facilitate transactions. Indeed, according to Wikipedia, there are currently more than 100 000 merchants accepting BTC as a form of payment (online or offline with wallet readers). Financial technology (‘Fintech’) is catching up with this market and some new companies try to compete with the traditional payment networks (Mastercard, Visa and others) by launching plastic cards linked with crypto-wallets (primarily Bitcoin).

Santander bank has expressed an interest in exploring this market further. It is certain that if the market for cryptocurrencies keeps growing at this pace, there will be a lot more challenger fintech firms launching new products that will make it easier to use digital currencies in everyday life.

Cryptocurrencies, therefore, are likely to have a significant impact on the way we pay for our transactions. They can be used to lower transaction costs (e.g. by simplifying the process of sending money abroad), speed up the processing of payments, facilitate microfinancing and transactions in some of the poorest places on earth – where the closest bank may be 50 miles away or further from where people live).

But there is a dark side to these products. They have been linked to tax-evasion for instance, as many people who trade digital currencies fail to declare capital gains to national tax authorities. They can be used to overcome capital controls and other restrictions imposed by national governments (the case of Greece comes to mind as a recent example).

They have also been blamed for facilitating illegal trading activities, such as in drugs and weapons, due to the anonymity that some of these coins are thought to offer to their users – although quite often they are much easier to trace than their users believe.

Cryptocurrencies do have the potential to change the way we live. They also have the potential to become the biggest Ponzi scheme in the history of mankind.

Over the next few months, I will write a number of blogs to explore the literature on the economics of cryptocurrencies, and discuss some of the major challenges that needs to be overcome if this technology is to become mainstream.

Bitcoin
Bitcoin was created in 2009 by an unknown person, or people, using the alias Satoshi Nakamoto. It is a digital currency in the form of a line of computer code. Bitcoins are like ‘electronic cash’ which can be held or used for transactions, with holdings and transactions heavily encrypted for security – hence it is a form of ‘crytocurrency’. People can buy and sell bitcoins for normal currencies as well as using them for transactions. People’s holdings are held in electronic ‘wallets’ and can be accessed on their computers or phones via the Internet. Transfers of bitcoins from one person or organisation to another are recorded in a public electronic ledger in the form of a ‘blockchain‘.

The supply of bitcoins is not controlled by central banks; rather, it is determined by a process known as ‘mining’. This involves individuals or groups solving complex and time-consuming mathematical problems and being rewarded with a new block of bitcoins.

The supply of bitcoins is currently growing at around 150 per hour and the current supply is around ₿16.7 million. However, the number of new bitcoins in a block is halved for every 210,000 blocks. This means that the rate of increase in the supply of bitcoins is slowing – the number generated being halved roughly every four years. The supply will eventually reach a maximum of ₿21 million, probably sometime in the next century, but around 99% will have been mined by around 2032.

The bitcoin bubble
The price of bitcoins has soared in recent months and especially in the past two. On 4 October, the price of a bitcoin was $4226; by 7 December it was nearly four times higher, at $16,858 – a rise of 399% in just nine weeks. Many people have claimed that this is a bubble, which will soon burst. Already there have been severe fluctuations. By December 10, for example, the price had fallen at one point to $13,152 – a fall of nearly 22% in just two days – only to recover to over $15,500 within a few hours.

So what determines the price of bitcoin? The simple answer is very straightforward – it’s determined by demand and supply. But what has been happening to demand and supply and why? And what will happen in the near and more distant future?

As we have seen, the supply is limited by the process of mining, which allows a relatively stable, but declining, increase. The explanation of the recent price rise and what will happen in the future lies on the demand side. Increasing numbers of people have been buying bitcoin, not because they want to use it for transactions, whether legitimate or illegal over the dark web, but because they want to invest in bitcoin. In other words, they want to hold bitcoin as an asset which is increasing in value. These people are known as ‘hodlers’ – a deliberate misspelling of ‘holders’.

But this speculation is of the destabilising form. The more prices have risen, the more people have bought bitcoin, thus pushing the price up further. This is a classic bubble, whereby the price does not reflect an underlying value, but rather the exuberance of buyers.

The problem with bubbles is that they will burst, but just when is virtually impossible to predict with any accuracy. If the price of bitcoins falls, what will happen next depends on how the fall is interpreted. It could be interpreted as a temporary fall, caused by some people cashing in to take advantage of the higher prices. At the same time, other people, believing that it is only a temporary fall, will rush to buy, snapping up bitcoins at the temporary low price. This ‘stabilising speculation’ will move the price back up again.

However, the fall in price may be seen as the bubble bursting, with even bigger falls ahead. In this case, people will rush to sell before it falls further, thereby pushing the price even lower. This destabilising speculation will amplify the fall in prices.

But even if the bubble does burst, people may believe that another bubble will then occur and, once they think the bottom has been reached, will thus start buying again and there will be a second speculative rise in the price.

The crash could be very short-lived. This happened with the second biggest cryptocurrency, Ethereum. On 21 June this year, the price at the beginning of the day was $360. It then began to fall during the say. Once its price reached $315, it then collapsed by 96% to $13 with massive selling, much of it automatic with computers programmed to sell when the price falls by more than a certain amount. But then, on the same day, it rebounded. Within minutes it had bounced back and was trading at $337 at the end of the day. It is now trading at around $450 – up from around $300 four weeks ago.

Whether the bubble in bitcoin has more to inflate, when it will burst, and when it will rebound and by how much, depends on people’s expectations. But what we are looking at here is people’s expectations of what other people are likely to do – in other words, of other people’s expectations, which in turn depend on their expectations of other people’s expectations. This situation is known as a Keynesian Beauty Contest (see the blog, A stock market beauty contest of the machines). Perhaps we need a crystal ball.